Although until recently Dromaeosaurus was known almost exclusively from a skull and some fragmentary bones found by Barnum Brown in 1914, in the Judith River Formation in Alberta, Canada, it has given its name to a family of dinosaurs - the dromaeosaurids. Similar in most ways to its better understood cousins Deinonychus and Velociraptor, Dromaeosaurus was a small, birdlike theropod with a claw that resembled a switchblade on the second toe of each foot. Even though new evidence of Dromaeosaurus has come to light in recent times, the scarceness of its fossil remains suggests that it may have been a rare theropod.

One feature common to all dromaeosaurids was the extreme stiffness of their tails. The tails of most theropods were stiffened, at least for part of their length. This relative inflexibility was caused by the lengthening of the attachment processes (bony rods known as zygapophyses) on the vertebrae. In the dromaeosaurids, however, these rods became greatly elongated, each of them extending over several vertebrae and effectively bracing them together. As a result of this, the thin tails of the dromaeosaurids became completely inflexible. The stiff tail would have helped Dromaeosaurus in pursuing prey by acting as an effective counterbalance behind the hip.

The world of Dromaeosaurus was filled with giant ceratopsians, duckbills, pachycephalosaurs, ankylosaurs, and tyrannosaurids such as Albertosaurus. An individual Dromaeosaurus would probably have been regarded as no more than a minor nuisance by most of these, but it would have been a source of terror to smaller dinosaurs and other vertebrates in its territory. Hunting in groups, however, may well have given Dromaeosaurus the capacity to target and bring down much larger prey.